def fun_checkout(money):
    money_old = sum(money)
    money_new = money_old
    if 500<=money_old<1000:
        money_new = '{:.2f}'.format(money_old * 0.9)
    elif 1000 <= money_old <=2000:
        money_new = '{:.2f}'.format(money_old * 0.8)
    elif 2000 <= money_old <= 3000:
        money_new = '{:.2f}'.format(money_old * 0.7)
    elif money_old>3000:
        money_new = '{:.2f}'.format(money_old * 0.6)
    return money_old,money_new
print("\n开始结算......\n")
list_money =[]
while True:
    inmoney = float(input("输入商品金额(输入0表示输入完毕):"))
    if int(inmoney) == 0:
        break
    else:
        list_money.append(inmoney)
money = fun_checkout(list_money)
print("合计金额：",money[0],"应付金额:",money[1])